Air-operated cutting device

ABSTRACT

A tool for cutting off a part of a sheet of material from a receiving roller and tucking the cut edge portion around said roller, so that it continues to wind thereon comprising a housing, a knife mounted for sliding in and out of an end of said housing, a spring for biasing said knife so that it tends to return to a protected position in said housing, a piston with a rod connected to said knife, and a connection from a source of compressed air to said piston, said connection branching beneath said knife, so that when air is released to move the knife so that it protrudes from said housing, air is simultaneously released to act on the cut edge portion of said sheet of material.

United States Patent Ramiccio [4 1 June 27, 1972 [54] AIR-OPERATED CUTTING DEVICE [22] Filed: May21, 1970 [21] App1.No.: 39,359

[56] References Cited UNITED STATES PATENTS 2,656,600 10/1953 Barbee ..30/123.3 2,854,745 10/1958 Braverman 3,155,011 11/1964 Hyskell ..30/166 X Primary Examiner-Andrew R. Juhasz Assistant Examiner-Michael Koczo, Jr. Attomey-Thomas W. Kennedy [5 7] ABSTRACT A tool for cutting ofi' a part of a sheet of material from a receiving roller and tucking the cut edge portion around said roller, so that it continues to wind thereon comprising a housing, a knife mounted for sliding in and out of an end of said housing, a spring for biasing said knife so that it tends to return to a protected position in said housing, a piston with a rod connected to said knife, and a connection from a source of compressed air to said piston, said connection branching beneath said knife, so that when air is released to move the knife so that it protrudes from said housing, air is simultaneously released to act on the cut edge portion of said sheet of material.

8 Claims, 5 Drawing Figures PATENTEDJUNEY I972 3.672.051

INVENTOR. v GERALD S- RAMICCIO l6 jmm- F ATTORNEY AIR-OPERATED CUTTING DEVICE SETTING AND OBJECTS OF THE INVENTION 7 This invention relates to a cutting device or knife for the cutting of sheets while being rolled up or in motion, especially films of plastic material.

The principal use of this knife is in the plastic industry where films of polyethylene or other plastic material is produced.

The knife is attached to an air line on each machine for winding up such material. When a button on the top of the knife is depressed and held down, compressed air flows thru a length of tubing and comes out a nozzle opening just below the cutting edge of the blade of the knife. At the same time, the air forces the blade out of an enclosing housing by use of a piston which is spring-biased for return. When the button is released the knife blade retracts and the air is cut off. The angle of the air nozzle is adjustable for either a left or right handed person.

The purpose of the knife is to aid the machine operator in making a safe transfer of film from one core to another while in production. At the present time, an operator has to cut the film with one hand and tuck the cut edge portion onto the receiving core with the other hand, to get a new roll started.

With the use of my air-knife, an operator needs only to cut the film and the air forces the cut edge portion of the sheet onto a winding core, making a safe transfer.

Many accidents have occurred with the standard cutting knife, as the operator's hand is sometimes pulled into the roll, resulting in a broken arm when he tucks the film around the core.

An object of my invention is to provide for safely directing the cut edge portion of a film onto a receiving roller or core.

Another object is the provision of a housing with a longitudinally slidable blade, a spring-biased actuating piston connected thereto, and a manuallycontrolled valve between said piston and a source of compressed air so that the blade may be exposed as needed to cut such a film, or released to be withdrawn into said housing.

Other objects and advantages will become apparent as the description proceeds in the drawings, wherein like reference characters denote like parts in the several views.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing my device in use.

FIG. 2 is a side elevational view of my device, with the cutting member or knife thereof in extended position, ready for use.

FIG. 3 is an end elevational view of the device, from the left thereof as viewed in FIG. 2.

FIG. 4 is a fragmentary longitudinal sectional view of the device on the line IV-IV of FIG. 3, in the direction of the arrows, which thus shows the interior of one of the housing sections and the parts enclosed by said housing.

FIG. 5 is a transverse sectional view of the device, as on the line V--V of FIG. 4, in the direction of the arrows.

DETAILED DESCRIPTION Referring to the drawings in detail, and first considering FIGS. 2 to 5, inclusive, there is shown one embodiment of my cutting device 11 comprising a housing 12 divided into two sections or parts 13 and 14 along a longitudinal plane, as illustrated in FIGS. 3 and 5. These parts when assembled may be held together by screws or other securing devices, such as indicated at 15. The outer surface of the housing is desirably contoured, as indicated at 16, to receive fingers of a hand, allowing for firm gripping. The front or outer end portions of the housing sections 13 and 14 are desirably provided with complementary portions forming an upstanding prong 16a, the portions of which may be held together by one of the screws 15.

The sections 13 and 14 are provided with complementary notches in the front wall portions 17 leaving a slot 18 in which is slidably mounted a knife 19, desirably a single edged razor blade. Said blade is provided with a pair of apertures 21 and 22 for receiving means, such as a screw 23, to secure it in a holder 24, presenting one end portion or the other for use, thereby obtaining double the life for the blade. Access to the screw 23 may be provided for by a slot 20 in the section 14. The holder 24 is biased to a retracted position by a coiled return spring 25, the outer end of which is secured to the rear wall of the holder by a plate 26 and the inner end of which is attached to a fixed part of the housing 12.

In the present embodiment, the housing parts have partition sections 27 and 28, said sections being provided with notches at their engaging edges, forming an aperture 29 in which reciprocates the rod 31 of a piston 32 for operating the knife 19. The rear or right hand end of the spring 25 is anchored to the partition part 28 by suitable means, here shown as a peg or stud 33 projecting toward the notched portion of the partition part 27, being desirably received in a cavity therein, and over which is hooked the adjacent end portion of the knife return spring 25 to apply the. desired tension thereto. The piston rod 31 may have a slot 34 to slidably receive the stud 33.

The piston 32 reciprocates in a cylinder 35 carried on and receiving compressed air from the upper branch of a desirably copper tube or pipe 36, in turn connected to a suitable source 37 after passing through the rear wall 38 of the housing 12. Air to both upper and lower branches of the pipe 36 is controlled by a valve 39 which is biased to closed position by a coil spring 41 in which reciprocates the valve stem 42. An air control button 43 is mounted on the outer end of the stem 42 and adapted to be manually operated against the force of the spring 41 to open the valve 39 and admit air to the cylinder 35, to move the knife 19 to operative position against the force of the return spring 25.

Opening of the valve 39 also allows air to flow through the lower branch of the pipe 36 and on out of the housing through a ball and socket joint 44, from which it discharges through a spout with an outlet opening 45 in the direction desired, as determined by the movement of the spout about the joint 44. This discharge of air is near the sharp edge, as will be seen from FIGS. 1, 2 and 4.

OPERATION A use for which my air-knife 11 is adapted is illustrated in FIG. 1. Here it is assumed that a film or sheet 46 of plastic material, moving from a supply, now shown, is to be wound around a roll or core 47, turning on and by a carrying shaft, after cutting off a part 48 thereof to be wound on a receiving roll or core 49, turning on and by its shaft. This was formerly done by an operator holding a knife in his right hand 50, unless he was left-handed, and cutting the film with said knife, while using his other hand 51 to direct or tuck the cutend of the film 46 between the core 47 and a guiding core or lay-on roll 52.

In accordance with my invention, the operator holds the airknife 11, in his right hand, if he is right-handed, and cuts from left to right across the film 46, after setting the spout 45 at the proper angle to tuck the cut edge of the film 46 between its core 47 and the lay-on or guiding roller 52 while turning on its carrying shaft, without danger of his left hand and arm. The portion of the film cut off is allowed to be rolled up on the core 49. If the operator is left-handed, he holds the air-knife in his left hand and, after properly setting the spout 45, cuts from right to left while allowing the air jet to tuck in the cut edge of the film, instead of using his right hand for that purpose.

Having now described my invention in detail in accordance with the requirements of the Patent Statutes, those skilled in this art will, within the scope of the claims, have no difficulty in making changes or modifications in the individual parts or their relative assembly in order to meet specific requirements or conditions.

I claim:

1. An air-operated cutting device, especially adapted to sever a part of a sheet of material as it passes off a core about which it is being wound on to a receiving roller and simultaneously tucking in the advancing cut edge portion of the remainder between said core and an associated guiding roller so that it continues to be guided around said core, comprising a knife with a lateral cutting edge, a housing to be held in the hand of an operator, means mounting said knife for movement from said housing to operative position, exposing a cutting edge portion thereof for use, or withdrawal into said housing for protection, a spring biasing said knife to retracted position in said housing, a tube connecting from a source of compressed air to said housing, means for controlling the discharge of air from said tube to push out the knife to its operative position against the force of the spring, or allow the spring to retract the knife into said housing, said tube having a branch for using a stream of said compressed air adjacent the cutting edge of the knife when exposed, so as to without manually contacting said sheet, effect the tucking in of the advancing cut edge portion of the remainder between the core and said guiding roller, while turning, so that it winds properly on said core.

2. A device as recited in claim 1, wherein the housing is generally hollow cylindrical, its outer surface is contoured to receive fingers of a hand, allowing for firm gripping, and the front end portion has a rearwardly curved prong to allow for hanging said device when not in use.

3. A device as recited in claim 1, wherein the housing is divided longitudinally and when the parts are assembled they are held together by screw devices.

4. A device as recited in claim 1, wherein the housing is generally hollow cylindrical, has front and rear walls and a partition dividing said housing into knife-holding and airreceiving compartments, a tube passes through and is positioned by said rear wall and said partition, and the front wall has a slot in which the knife is longitudinally slidable.

5. A device as recited in claim 1, wherein the means for controlling the discharge is a valve in the tube, a button nonnally protruding from a side of the housing, spring-biased to outer position, and manually movable inward to open said valve and release air to said tube branch for the discharge of air against said sheet.

6. A device as recited in claim 5, wherein there is a transverse partition in the housing, the rear end of the knife spring is secured thereto, a holder secured to the other end of said spring, a screw holding one end portion of said knife in said holder, an air cylinder to receive compressed air from said source, a piston therein with a rod passing through said partition and spring and secured to said holder.

7. A device as recited in claim 6, wherein there is an aperture in said front wall at the level of the tube branch, and a nozzle projecting from said branch through said front wall and articulated with respect to said branch to allow said nozzle to direct air therefrom to said sheet.

8. A method of severing sheets of material while being rolled on cores, comprising cutting across each sheet as it passes off a core on which it is being wound around and on to a receiving roller and simultaneously tucking in the advancing cut edge of each sheet between its core and an associated guiding roller. 

1. An air-operated cutting device, especially adapted to sever a part of a sheet of material as it passes off a core about which it is being wound on to a receiving roller and simultaneously tucking in the advancing cut edge portion of the remainder between said core and an associated guiding roller so that it continues to be guided around said core, comprising a knife with a lateral cutting edge, a housing to be held in the hand of an operator, means mounting said knife for movement from said housing to operative position, exposing a cutting edge portion thereof for use, or withdrawal into said housing for protection, a spring biasing said knife to retracted position in said housing, a tube connecting from a source of compressed air to said housing, means for controlling the discharge of air from said tube to push out the knife to its operative position against the force of the spring, or allow the spring to retract the knife into said housing, said tube having a branch for using a stream of said compressed air adjacent the cutting edge of the knife when exposed, so as to without manually contacting said sheet, effect the tucking in of the advancing cut edge portion of the remainder between the core and said guiding roller, while turning, so that it winds properly on said core.
 2. A device as recited in claim 1, wherein the housing is generally hollow cylindrical, its outer surface is contoured to receive fingers of a hand, allowing for firm gripping, and the front end portion has a rearwardly curved prong to allow for hanging said device when not in use.
 3. A device as recited in claim 1, wherein the housing is divided longitudinally and when the parts are assembled they are held together by screw devices.
 4. A device as recited in claim 1, wherein the housing is generally hollow cylindrical, has front and rear walls and a partition dividing said housing into knife-holding and air-receiving compartments, a tube passes through and is positioned by said rear wall and said partition, and the front wall has a slot in which the knife is longitudinally slidable.
 5. A device as recited in claim 1, wherein the means for controlling the discharge is a valve in the tube, a button normally protruding from a side of the housing, spring-biased to outer position, and manually movable inward to open said valve and release air to said tube branch for the discharge of air against said sheet.
 6. A device as recited in claim 5, wherein there is a transverse partition in the housing, the rear end of the knife spring is secured thereto, a holder secured to the other end of said spring, a screw holding one end portion of said knife in said holder, an air cylinder to receive compressed air from said source, a piston therein with a rod passing through said partition and spring and secured to said holder.
 7. A device as recited in claim 6, wherein there is an aperture in said front wall at the level of the tube branch, and a nozzle projecting from said branch through said frOnt wall and articulated with respect to said branch to allow said nozzle to direct air therefrom to said sheet.
 8. A method of severing sheets of material while being rolled on cores, comprising cutting across each sheet as it passes off a core on which it is being wound around and on to a receiving roller and simultaneously tucking in the advancing cut edge of each sheet between its core and an associated guiding roller. 